Need some serious advice!!!

So I’ve been have in law issues. Lately I’ve notice that since there is another baby in the family by the favorite child. My baby is being treated deferentially It started out with little things like helping out with things that they would have never done with me. which I had also offered to do. But recently it like they never want to see my child and make up reason why he can’t come over but have the other grandchild over almost every other day taking days off to spend time with him ect. My son is older and he’s starting to notice these things. Which is make me angry. Also should mention that They have never really like me while it has never been addressed what the reasoning is. I’m just sick and tired of the passive aggressive behaviors and I respect that my husband want to have a relationship with them I don’t believe it’s healthy for me or my son anymore. And before the ladies come in with the your jealous this and that there is a whole lot more inappropriate stuff that has happened and been said. Like how wild my son is and that was a better word than they chose. Which I don’t get because when they have him they would condone the behavior and me and my husband would never let him get away with it if we were present. Or make sure baby toys are washed and bedding cleaned for her child but I would have to either wash it or mention that it had gotten dirty myself. Or constantly babying her son but telling mine to suck it up and mentioning how much of a cry baby he is. I just think it’s a toxic environment and don’t believe that mention it to them any further would be worth while. And don’t want my child to feel like they are not worth someone’s time because of who their parents are.